If a flight is listed with one major airline but they have you flying on another through their arrangements, what luggage fee applies? Tricky!

-Shelley

Dear Shelley,

This is a pretty tricky question. I asked American Airlines, which has domestic partnerships with Alaska Airlines and Hawaiian Airlines, and a spokesperson told me "the baggage policies of the airline actually flying the flight take precedence if they do not coincide with ours." This makes sense, when you think about it, because you're paying the airline that actually carries your bag.

"What if I hold an itinerary that includes travel on a codeshare or Star Alliance partner airline?

You should check on the policies of the operating carrier."

Great, but what about connecting itineraries where one airline operates the first segment and another airline operates the second (or third)? In nearly all cases, your bags will be checked through to your destination, so you pay the fee to the airline operating the first segment. On its site, United confirms this, saying, "If, as part of your itinerary, you will travel on different airlines each way on a round-trip ticket, the baggage policy of the first flight in each direction will apply."

Continental, United, and US Airways are all partners via star alliance, a network of global airlines. All three airlines charge identical bag fees ($23 online/$25 airport for the first, $32 online/$35 airport for the second) and, as you may have gathered, all three allow you to pay the fee online. This, at least, means you won't get stuck with a higher fee if you book with one but fly with the other. You just need to find out ahead of time which airline you'll be flying if you want to pay the fee online.

With American and Delta, however, the situation is not so simple. American, which doesn't have an online bag fee option, partners with Hawaiian, which does. (It also partners with Alaska, which doesn't.) So frequent American customers flying on a codeshare with Hawaiian may not think to pay their fee online. The good news is that both Alaska and Hawaiian have cheaper fees, even, in the case of Hawaiian, if you pay at the airport.

Delta's domestic partners are Alaska and American Eagle, neither of which have an online option either. Further, while Alaska's fees are cheaper than Delta's, American Eagle's fees is equal to Delta's airport fees. This means Delta customers lose the benefit of that carrier's online discount.

Whew! Complicated enough for you?

As for the low-cost carriers, neither Southwest, AirTran, JetBlue, or Virgin America have major domestic partnerships. And, as you no doubt know, JetBlue doesn't charge for the first bag and Southwest doesn't charge for the first two.